1. Field of the Invention
The present invention relates to a probe card having a deeply recessed trench and a method for manufacturing the same, and more particularly to a probe card having a deeply recessed trench and a method for manufacturing the same wherein the probe card is manufactured using the single crystalline silicon substrate and an oxide film or a nitride film is used as an insulating film to facilitate a signal separation between the probes, wherein the probe is movable only in a vertical direction using a trench to improve a electrical or a mechanical characteristic and to automatically limit the vertical movement thereof within a predetermined range, and wherein a pitch may be reduced so as to correspond to a decreasing distance between pads, a flatness of a probe tip may be maintained within a few micrometers using a semiconductor manufacturing process, 32 simultaneous parallel testing is possible contrary to a convention probe card, a wafer level testing is possible, and time and cost for a wafer testing are reduced.
2. Background of the Invention
Generally, during a manufacturing process of a semiconductor integrated circuit such as a memory device, a non-memory device or a logic device, a test for determining defectiveness of each of chips is performed after manufacturing the chips on a wafer. The test is carried out by connecting the probe card to a probe testing device and applying a signal to the chip to be tested with probe tips of the probe card being in contact with pads of the chip to be tested.
Since a force of 1 gram force per tip is applied to between the probe tips of the probe testing device and testing wafer including the chip to be tested, the probe tip must withstand this force, and must have a reliability to endure about one million contacts with the wafer. Moreover, a contact resistance of the probe tip should be less than 1 ohm, and a pitch should be less than 45 μm to correspond to a miniaturized semiconductor chip design.
A detailed description of a conventional probe card is disclosed in Korean Patent Application No. 10-2002-0076050 filed on Dec. 2, 2002 by the applicant, titled “Cantilever-Type Probe Card and Method for manufacturing the Same Using Silicon Micromachining Technology”.
As disclosed in Korean Patent Application No. 10-2002-0076050, the conventional probe card is disadvantageous in an aspect of carrying out mass testing of wafer. For example, in accordance with U.S. Pat. No. 6,087,840 which is referred to as a conventional art in Korean Patent Application No. 10-2002-0076050, a pitch of a pad cannot be reduced below 50 μm because a tungsten needle (probe needle) is manually mounted, and an entire wafer cannot be tested in a single test so that relatively more time and cost is required. Other conventional arts disclosed in Korean Patent Application No. 10-2002-0076050 are also disadvantageous in that the probe card is sensitive to external shock or a temperature change, the pitch cannot be reduced below 50 μm, and a parallel test is difficult. Moreover, a wafer level test wherein the entire wafer is tested at once cannot be carried out, and each chip should be tested separately, resulting in a long testing time and a high testing cost.
In order to solve such problem, Korean Patent Application No. 10-2002-0076050 discloses a cantilever type probe card and a method for manufacturing the same wherein a through-hole is formed at an edge portion of a silicon substrate such as SOI (Silicon On Insulator) substrate, the through-hole is filled up with a conductive layer, a spring and a tip are then formed at a center portion of the SOI substrate by a photo lithography and etching process, a metal line electrically connected to the conductive layer in the through-hole is formed, and the conductive layer in the through-hole is then bonded to, a metal line of a printed circuit board.
FIG. 1 is a cross-sectional view illustrating a configuration of a conventional probe card.
As shown, the cantilever type probe card in accordance with Korean Patent Application No. 10-2002-0076050 comprises a printed circuit board 110 and SOI substrate 120. A through-hole 125 is formed in the SOI substrate 120 to be connected to the printed circuit board 110, an end portion 130 of a tip and a spring 135 are formed, a conductive material 138 is formed so that an electrical signal may be applied from printed circuit board 110 to a pad 165 of a wafer the substrate 160 to be tested. The end portion 130 of the tip and the spring 135 are hereinafter referred to as a probe tip and a probe beam, respectively.
However, while a configuration of the cantilever type probe card in accordance with Korean Patent Application No. 10-2002-0076050 is advantageous in that a pitch between tips may be reduced and more than 32 parallel tests and a wafer level test are possible, a contact between the probe beams or a damage of the probe beam may occur due to a horizontal movement of the probe beams when a force is applied diagonally instead of vertically. Actually, when a pressure is applied to the probe beam, a possibility of the damage and malfunction of the probe tip is increased during an actual test because a lateral force as well as a completely vertical force exists.
In order to solve above-described problem, Korean Patent Application No. 10-2003-0022937, filed by Yulim Hitech Inc. on Apr. 11, 2003 and published on Oct. 10, 2004 titled “Needle Assembly of Probe Card” disclose a configuration wherein a horizontal movement of a probe tip due to a lateral force component is prevented by forming a needle moving hole.
FIG. 2 is a cross-sectional view illustrating a configuration of the probe card disclosed by Korean Patent Application No. 10-2003-0022937. As shown, in accordance with the probe card disclosed in Korean Patent Application No. 10-2003-0022937, a needle plate 220 is allowed to only move vertically through a movable gap 215 and a moving hole 210 even when the lateral force component with respect to the needle plate 220 exists to reduce the possibility of the damage and malfunction of the probe tip.
Particularly, in accordance with the configuration of the probe card disclosed by Korean Patent Application No. 10-2003-0022937, the needle plate 220 moves inside the moving hole 210, that is, in the vertical direction to solve an instability that may occur when a width of the probe beam is smaller than a thickness thereof as a distance between pads is reduced. Therefore, a probe having a stable configuration for corresponding to the reduced pitch is provided.
However, while the configuration of the probe card disclosed by Korean Patent Application No. 10-2003-0022937 reduces the possibility of the damage and malfunction of the probe, and the pitch, a metal line process cannot be carried out directly on the silicon substrate so that the metal line process should be carried out through the interface board 240 and a metal line for testing is formed between the interface board 240 and the printed circuit board (not shown) because of the moving hole 210 in the silicon substrate. Therefore, a configuration of the testing device is very complex.